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1.
S. Xie  Y. Cui    T. Zhang  Z. Li 《Journal of fish biology》2000,57(4):867-880
Feeding ecology of three small fish species, Hypseleotris swinhonis, Ctenogobius giurinus and Pseudorasbora parva was studied seasonally in the Biandantang Lake, a small, shallow lake in central China. Gut length, adjusted for total body length, was significantly higher in spring than in other seasons for all the three species. Seasonal changes in gut length were not associated with changes in food quality. Weight of fore-gut contents, adjusted for body weight, was significantly higher in winter and spring than in summer and autumn in H. swinhonis and C. giurinus , and significantly higher in autumn than in spring and summer for P. parva. Percentage of empty fore-guts was highest in summer and lowest in spring for H. swinhonis and C. giurinus , and highest in winter and lowest in autumn for P. parva. Diet of the three small fishes showed apparent seasonal changes, and these changes reflected partly the seasonal fluctuations of food resources in environment. Diet breadth was high in winter and low in autumn for H. swinhonis , high in winter and low in spring and summer for C. giurinus , and high in autumn and low in spring for P. parva. Diet overlaps between pairs of species were biologically significant in most cases, except between H. swinhonis and P. parva in summer and autumn and between C. giurinus and P. parva in autumn.  相似文献   

2.
Circadian rhythms in noradrenergic (NE) and dopaminergic (DA) metabolites and in cyclic nucleotide production were measured in discrete regions of rat brain. A circadian rhythm was found in the concentration of the NE metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG), in the hippocampus. No MHPG rhythm was found in frontal, cingulate, parietal, piriform, insular or temporal cortex, or in hypothalamus. Circadian rhythms in the concentration of the NE metabolite, 3,4-dihydroxyphenylglycol (DHPG), occurred in occipital and parietal cortex and hypothalamus, with no rhythm observable in temporal or insular cortex, hippocampus, pons-medulla or cerebellum. The 24-hr mean concentration of MHPG varied 3.5-fold, highest in cingulate and lowest in parietal, temporal and occipital cortex. The 24-hr mean concentration of DHPG varied 6-fold, highest in hypothalamus and lowest in parietal cortex. Circadian rhythms in the concentration of the DA metabolite, homovanillic acid (HVA), were found in olfactory tubercle, amygdala and caudate-putamen, but not in nucleus accumbens. A circadian rhythm in the concentration of the DA metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC), occurred in nucleus accumbens, but not in olfactory tubercle or caudate-putamen. The mean 24-hr concentration of HVA was highest in caudate-putamen, intermediate in nucleus accumbens, and lowest in olfactory tubercle and amygdala. The mean 24-hr concentration of DOPAC was highest in nucleus accumbens and lower in olfactory tubercle and caudate-putamen. Circadian rhythms were found in the concentration of cyclic GMP (cGMP) in all regions measured except parietal cortex. The mean 24-hr concentration varied 128-fold, highest in nucleus accumbens, frontal poles, and hypothalamus and lowest in cingulate cortex. Circadian rhythms in cyclic AMP (cAMP) concentration were found in piriform, temporal, occipital, cingulate, and parietal cortex, amygdala and nucleus accumbens. No rhythms were found in frontal or insular cortex, hypothalamus, hippocampus, caudate-putamen or olfactory tubercle. The 24-hr mean cAMP concentration varied 4-fold, highest in parietal cortex and lowest in caudate-putamen and amygdala. Norepinephrine metabolites and dopamine metabolites were rhythmic in few regions. It is, therefore, unlikely that the rhythmicity measured in adrenergic receptors is, in general, a response to rhythmic changes in adrenergic transmitter release. The putative second messenger response systems, especially cGMP, were more often rhythmic. The rhythms in cGMP are parallel in form and region to those in the alpha 1-adrenergic receptor and may act as 2nd messenger for that receptor.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

3.
猪激素敏感脂酶和甘油三酯水解酶基因组织表达特性研究   总被引:1,自引:0,他引:1  
以八眉猪为研究对象,采用RT-PCR和Western blot方法对猪激素敏感酯酶(HSL)和甘油三酯水解酶(TGH)基因组织表达特点进行了研究。RT-PCR半定量检测显示,HSL基因的mRNA在检测的7种组织中都有表达,其中在脂肪组织表达量较高,中等程度表达于心脏、肝脏、肺、脾和肾脏。TGH基因在7种组织也均有表达,其中肝脏和脂肪组织表达量较高,心脏和肾脏次之,脾脏和肺脏表达量较低。Western blot检测显示,HSL基因在大网膜脂肪和皮下脂肪表达量最高,而在肾脏中没有检测到表达,其他组织中中度表达;TGH基因在大网膜脂肪、皮下脂肪、肝脏、肺脏和脾脏组织中表达,其中在脂肪组织和肝脏组织中表达量最高,而在心脏和肾脏中没有检测到表达。以上结果表明:HSL和TGH基因存在转录后调控,这可能与其在不同组织中的功能差异有关。  相似文献   

4.
We examined the relationship between grip strength declines and muscle-tendon responses induced by long-term performance of a high-repetition, low-force (HRLF) reaching task in rats. We hypothesized that grip strength declines would correlate with inflammation, fibrosis and degradation in flexor digitorum muscles and tendons. Grip strength declined after training, and further in weeks 18 and 24, in reach limbs of HRLF rats. Flexor digitorum tissues of reach limbs showed low-grade increases in inflammatory cytokines: IL-1β after training and in week 18, IL-1α in week 18, TNF-α and IL-6 after training and in week 24, and IL-10 in week 24, with greater increases in tendons than muscles. Similar cytokine increases were detected in serum with HRLF: IL-1α and IL-10 in week 18, and TNF-α and IL-6 in week 24. Grip strength correlated inversely with IL-6 in muscles, tendons and serum, and TNF-α in muscles and serum. Four fibrogenic proteins, TGFB1, CTGF, PDGFab and PDGFbb, and hydroxyproline, a marker of collagen synthesis, increased in serum in HRLF weeks 18 or 24, concomitant with epitendon thickening, increased muscle and tendon TGFB1 and CTGF. A collagenolytic gelatinase, MMP2, increased by week 18 in serum, tendons and muscles of HRLF rats. Grip strength correlated inversely with TGFB1 in muscles, tendons and serum; with CTGF-immunoreactive fibroblasts in tendons; and with MMP2 in tendons and serum. Thus, motor declines correlated with low-grade systemic and musculotendinous inflammation throughout task performance, and increased fibrogenic and degradative proteins with prolonged task performance. Serum TNF-α, IL-6, TGFB1, CTGF and MMP2 may serve as serum biomarkers of work-related musculoskeletal disorders, although further studies in humans are needed.  相似文献   

5.
植物叶片的非结构性碳水化合物(NSC)不仅可以反应植物的碳供应状况,也能反应植物对外界环境的适应策略。利用传统的蒽酮比色法测定了东北3个典型森林生态系统(呼中、凉水和长白山)242种常见植物叶片的非结构碳水化合物,探讨了温带主要森林植物叶片NSC沿纬度梯度的变化趋势及其在物种-生活型-群落间的分布规律。实验结果表明:3个典型森林生态系统植物叶片可溶性糖、淀粉和NSC含量均呈偏正态分布,多数物种的含量偏中低水平;242种植物叶片可溶性糖、淀粉和NSC的平均含量分别为63.31、65.66和128.96 mg/g。在所调查的森林生态系统中,叶片可溶性糖、淀粉和NSC含量在不同生活型中表现各异。此外,乔木植物叶片的可溶性糖、淀粉和NSC含量从北到南呈递增趋势,呼中最低,凉水次之,长白山最高。乔木淀粉含量均表现为落叶树种大于常绿树种,可溶性糖和NSC含量变化趋势复杂。研究结果不仅为阐明东北主要森林生态系统植被碳代谢和生长适应对策提供数据基础,而且对理解植物对未来气候变化的响应机理提供数据支撑。  相似文献   

6.
Lipid content in mammalian oocytes or embryos differs among species, with bovine and porcine oocytes and embryos showing large cytoplasmic droplets. These droplets are considered to play important roles in energy metabolism during oocyte maturation, fertilisation and early embryonic development, and also in the freezing ability of oocytes or embryos; however, their detailed distribution or function is not well understood. In the present study, changes in the distribution and morphology of porcine lipid droplets during in vivo and in vitro fertilisation, in contrast to parthenogenetic oocyte activation, as well as during their development to blastocyst stage, were evaluated by transmission electron microscopy (TEM). The analysis of semi-thin and ultra-thin sections by TEM showed conspicuous, large, electron-dense lipid droplets, sometimes associated with mitochondrial aggregates in the oocytes, irrespective of whether the oocytes had been matured in vivo or in vitro. Immediately after sperm penetration, the electron density of the lipid droplets was lost in both the in vivo and in vitro oocytes, the reduction being most evident in the oocytes developed in vitro. Density was restored in the pronculear oocytes, fully in the in vivo specimens but only partially in the in vitro ones. The number and size of the droplets seemed, however, to have decreased. At 2- to 4-cell and blastocyst stages, the features of the lipid droplets were almost the same as those of pronuclear oocytes, showing a homogeneous or saturated density in the in vivo embryos but a marbled or partially saturated appearance in the in vitro embryos. In vitro matured oocytes undergoing parthenogenesis had lipid droplets that resembled those of fertilised oocytes until the pronuclear stage. Overall, results indicate variations in both the morphology and amount of cytoplasmic lipid droplets during porcine oocyte maturation, fertilisation and early embryo development as well as differences between in vivo and in vitro development, suggesting both different energy status during preimplantation development in pigs and substantial differences between in vitro and in vivo development.  相似文献   

7.
啮齿动物作用下退耕地山杏种子扩散与贮藏的季节变化   总被引:2,自引:0,他引:2  
啮齿动物对植物种子的取食和扩散影响种子的时空分布,继而影响种子的萌发和幼苗建成,因而在森林更新中起着重要作用.在国有济源市愚公林场,选择退耕地生境,于春季、夏季、秋季分别释放人工标记的山杏种子,观察啮齿动物扩散与埋藏山杏种子的季节性差异.结果表明:1)退耕地中的啮齿动物主要包括大林姬鼠、社鼠、黑线姬鼠;2)山杏种子扩散速率在春季显著慢于夏季,夏季显著慢于秋季;3)种子搬运量受季节和种子状态交互作用影响,春季显著少于夏季,夏季显著少于秋季;4)不同季节种子平均搬运距离不同,秋季不同状态种子的搬运距离均大于春季和夏季;5)啮齿动物对山杏种子的贮藏点大小多为1粒种子,少量为2、3粒种子,且贮藏点大小与季节间存在显著的交互作用,春季单粒种子的贮藏点数量显著少于夏季和秋季,而夏季与秋季的贮藏点则倾向于多粒种子;6)在夏季和秋季各有5枚(共释放1800枚)被啮齿动物分散贮藏的山杏种子建成幼苗.  相似文献   

8.
Skakun VN  Aseev MV  Shawi A  Baranov VS 《Genetika》1999,35(9):1280-1288
The allele polymorphism of the AGC short tandem repeat (STR) of exon 1 of the androgen receptor (AR) gene located in Xq11-12, ATCT STR of intron 40 of the von Willebrand factor (vWF) gene located in chromosome 12p12, and AGAT STR of an anonymous DNA sequence (STRX1) from the short arm of the X chromosome was analyzed in the Georgian, Uzbek, and Russian populations. Polymerase chain reaction (PCR) with DNA of unrelated persons revealed 14 AR, 7 vWF, and 7 STRX1 alleles in Georgians; 14, 8, and 6 alleles, respectively, in Uzbeks; and 16, 8, and 9 alleles, respectively, in Russians. The heterozygosity at these STR was 0.61, 0.78, and 0.46 in Georgians; 0.60, 0.83, and 0.44 in Uzbeks; and 0.80, 0.70, and 0.58 in Russians. The correspondence of genotype frequencies to the Hardy-Weinberg equilibrium was observed with AR STR in Russians and Uzbeks, STRX1 STR in Georgians, and vWF in all three populations. A significant deviation from the equilibrium was found for STRX1 in Russians and Uzbeks and AR in Georgians. The potential of individualization was 0.05 for AR, 0.13 for vWF, and 0.18 for STRX1 in Georgians; 0.04, 0.09, and 0.13, respectively in Uzbeks; and 0.05, 0.14, and 0.07, respectively, in Russians. The allele and genotype frequency distributions of each STR were analyzed in all three populations. Allele frequencies in the populations were compared by the Kolmogorov-Smirnov test. The Russian population significantly differed in allele frequencies of the three STR from Uzbeks and in those of STRX1 and AR from Georgians. Georgians and Uzbeks significantly differed in vWF and STRX1 frequencies. The possibility of using the three STR in molecular diagnosis of the corresponding monogenic diseases, population genetic studies, and personal identification is discussed.  相似文献   

9.
The ontogenetic trends in the expression of 25 isozymes in liver, gizzard, heart, and pectoralis muscle of White Leghorn chickens were examined using starch gel electrophoresis. Little change in expression during development was evident in liver S-AAT-A, GPI-A, S-ICDH-A, S-MDH-A and M-MDH-A, in gizzard S-ACON-A, ADH-A, GPI-A, HK-1, HK-3, ME-A PEP-1, and PGM-A, in heart ADH-A, HK-1, HK-3, ME-A, PEP-2, PGM-A, and LDH-A, in pectoralis M-ACON-A, S-ACON-A, ADH-A, HK-1, HK-3, ME-A, PEP-2, and PGM-A, and in liver, gizzard, and heart M-ACON-A, ALD-A, CK-A, G3PDH-A, HK-1, and PGDH-A. Increasing levels of activity were demonstrated in liver ADH-A, ME-A, and PEP-2, in heart M-MDH-A, S-ICDH-A, M-ICDH, and M-AAT-A, and in pectoralis LDH-A, LDH-B, G3PDH-3, ALD-A, CK-A, HK-2, and PGM-B. There was a decrease in the activity of HK-1 in liver and in PEP-1 and PGDH-A in pectoralis muscle throughout development. While CK-C is active in the embryonic pectoralis, CK-A is restricted to later developmental stages. Isozyme expressions in regions of the pectoralis containing fast and slow muscle fibers in 7-month-posthatch individuals were noted and found to be identical. The results underscore the need to use similar developmental stages and tissue samples in comparative electrophoretic studies of birds.This study was supported by Natural Sciences and Engineering Research Council of Canada Grant A9866 to J.P.B.  相似文献   

10.
广东大中型水库底泥重金属含量特征及潜在生态风险评价   总被引:17,自引:1,他引:17  
广东省45宗大中型水库底泥重金属含量分析评价结果表明:除Cr外,广东省大中型水库底泥中Cu、Zn、Pb和Cd含量均高于广东省土壤重金属含量背景值.广东省四大地理区域中,粤北地区大中型水库底泥Cu、Zn、Pb和Cd平均含量均为最高,分别为89.71、321.21、154.95mg/kg和1.46mg/kg;其次是粤东和粤中地区;粤西大中型水库底泥Cu、Zn、Pb和Cd平均含量均为最低,但Cr平均含量居四大区域之首,为130.81mg/kg.粤东和粤北大中型水库底泥重金属富集系数以Cd最高;粤中和粤西大中型水库底泥重金属富集系数则以Cu最大.总体而言,粤北大中型水库底泥重金属具有很强的潜在生态风险,粤东和粤中大中型水库底泥重金属潜在生态风险程度为中等;粤西大中型水库底泥重金属属于轻微生态风险程度.结果说明,广东省大部分地区大中型水库底泥的重金属潜在生态风险主要是由于底泥中Cd的潜在生态风险系数过高所造成.人为生产活动,特别是矿产开采造成的污染是广东省大中型水库底泥重金属潜在生态风险等级提高的主要原因.  相似文献   

11.
The distribution of vasotocin and mesotocin in the pituitary and central nervous system in male chickens was determined using radioimmunoassays. Neither peptide was detected in the pineal. Mesotocin, but not vasotocin, was detected in the cerebellum. Both peptides were found in the septal area, archistriatum, paleostriatum, optic lobe, anterior, medial and posterior hypothalamus, midbrain, pons, medulla oblongata, and the anterior and posterior pituitary. Equal amounts of the 2 peptides were present in the septal area, archistriatum and anterior hypothalamus whereas vasotocin was more abundant (2- to 10-fold) in the paleostriatum, optic lobe, midbrain, and pituitary. The amount of mesotocin was about twice that of vasotocin in the medulla oblongata and the medial and posterior hypothalamus. The wide distribution of vasotocin and mesotocin in extrahypothalamic sites in the central nervous system suggests that the peptides may, as in mammals, have a role in a variety of autonomic and endocrine regulatory processes in chickens.  相似文献   

12.
陈淳 《人类学学报》1983,2(4):331-408
通过中国十个重要细石器遗址中细石核的观察,对中国细石核的类型和工艺技术作一初步的区分和综合的比较,以探讨中国细石器传统在时间和空间上的分布特点。同时与发现于东北亚、西北美的细石核进行对比,从它们之间的异同来看这一地区在文化上的传承关系。  相似文献   

13.
Circadian rhythms were measured in alpha 1-, alpha 2- and beta-adrenergic, acetylcholine muscarinic (ACh), and benzodiazepine (BDZ) receptor binding in small regions of rat brain. Rhythms in alpha 1-receptor binding were measured in olfactory bulb, frontal, cingulate, piriform, parietal, temporal and occipital cortex, hypothalamus, hippocampus, pons-medulla, caudate-putamen and thalamus-septum. No rhythm was found in cerebellum. Rhythms in alpha 2-receptor binding were measured in frontal, parietal and temporal cortex, and pons-medulla. No rhythm was found in cingulate, piriform or occipital cortex, or hypothalamus. Rhythms in binding to beta-receptors were measured in olfactory bulb, piriform, insular, parietal and temporal cortex, hypothalamus and cerebellum. No rhythms were found in frontal, entorhinal, cingulate, or occipital cortex, hippocampus, caudate-putamen, or pons-medulla. Rhythms in ACh receptor binding were measured in olfactory bulb, parietal cortex and caudate-putamen. No rhythms were found in frontal or occipital cortex, nucleus accumbens, hippocampus, thalamus-septum, pons-medulla or cerebellum. Rhythms in BDZ receptor binding were measured in olfactory bulb, olfactory and occipital cortex, olfactory tubercle, nucleus accumbens, amygdala, caudate-putamen, hippocampus and cerebellum. No rhythms were found in parietal cortex, pons-medulla or thalamus-septum. The 24-hr mean binding to receptors varied between 3- and 10-fold, the highest in cortex and the lowest, usually, in cerebellum. The piriform cortex was particularly high in alpha 1- and alpha 2-adrenergic receptors; the nucleus accumbens and caudate, in ACh receptors; and the amygdala, in BDZ receptors. Most adrenergic and ACh receptor rhythms peaked in subjective night (the period when lights were off under L:D conditions), whereas most BDZ receptor rhythms peaked in subjective day (the time lights were on in L:D). Perhaps in the rat, a nocturnal animal, the adrenergic and ACh receptors mediate activity and the functions that accompany it, and the BDZ receptors mediate rest, and with it, sleep.  相似文献   

14.
为研究油茶(Camellia oleifera A)嫁接时穗条和砧木创伤后内源激素动态变化规律,解析影响砧穗嫁接面愈合的生理机制,为油茶砧穗愈合生长机理提供理论支持。以树龄6年的长林18号和53号的穗条和实生砧木为材料,按照芽苗砧嫁接方法切割穗条S0(0 min)、S10(10 min)、S40(40 min)和砧木茎段Z0(0 min)、Z10(10 min)后,利用液质联用法(HPLC-MS)测定吲哚乙酸(IAA)、脱落酸(ABA)、反式玉米素(TZR)、玉米素(Zeatin)、水杨酸(SA)和茉莉酸(JA)含量,分析不同时间段内源激素变化及品种间差异的关系。结果显示:创伤后18号的TZR、Zeatin和SA含量总体高于53号;18号IAA、SA和JA逐渐下降;TZR和Zeatin分别在S10和S0达最高值后下降;ABA在S10达最高值。53号IAA和JA爱S10达最高值后下降;TZR、Zeatin和SA在S10达低值后逐渐上升;ABA在S0达高值后逐渐下降。砧木茎段创伤前后激素含量除JA外18号高于53号;两品种Z0时激素含量下降,Z10后上升,仅53号ABA和SA含量在Z0达高值后下降。砧木茎段和根部激素含量在品种间除JA外18号高于53号,茎段的IAA、ABA高于根部,其他激素为根部高于茎段。激素比值在品种间和部位间差异明显;IAA/ABA、IAA/TZR、IAA/Zeatin和IAA/JA、ABA/TZR、ABA/Zeatin和ABA/JA比值为53号高于18号;穗条内SA/IAA为18号高于53号,SA/JA和SA/ABA为53号高于18号;砧木茎段均为18号高于53号;TZR/SA、TZR/JA比值在穗条和砧木茎段为18号高于53号。两品种创伤后IAA与JA极显著正相关,而IAA与SA,SA与JA在18号极显著正相关,53号极显著或显著负相关;53号TZR、Zeatin、SA间极显著或显著正相关,JA与TZR、Zeatin和SA极显著负相关。砧木茎段创伤后18号激素间为极显著或显著正相关;53号TZR和Zeatin与IAA、JA极显著正相关,与SA存在显著负相关,SA与JA有显著负相关。砧木茎段和根部间品种间仅在SA与各激素间相关性存在差异,其他激素间存在极显著正相关或负相关。综上所述,砧穗创伤后激素水平上18号在创伤面易于愈伤组织发育,而53号抗逆激素水平较高且与细胞分裂增殖类激素负相关,可能影响53号嫁接后愈合生长;嫁接应在创伤后10 min内较为适宜;砧穗间激素含量及比值的差异可能会影响后期嫁接部位形态重建以及穗条生长。  相似文献   

15.
1962—2010年甘肃省黄土高原区干旱时空动态格局   总被引:2,自引:0,他引:2  
借助ArcGIS 9.3和SPSS软件平台,根据甘肃省黄土高原区33个气象站1962—2010年气象资料,利用综合气象干旱指数(CI)从干旱率、干旱强度和干旱频率三方面对甘肃省黄土高原区近50年的干旱时空变化特征进行了分析。结果表明:春、秋季干旱率呈现显著增加趋势,夏、冬季干旱率呈略微增加趋势;夏季干旱频率最大,春季、秋季次之,冬季最少;春、秋季干旱以2000年来最为严重,夏季干旱以2000年以来、20世纪70年代和90年代均较严重,冬季干旱以20世纪80年代最为严重;甘肃省黄土高原区逐年干旱持续日数和干旱强度存在明显的年际波动,线性变化趋势明显;从空间分布来看,春、夏和秋季干旱多发区主要集中在甘肃省黄土高原区西北部,而106°E以西"临洮-通渭-天水"一线和庆阳东南部是干旱多发区变幅最大的地方,冬季干旱多发区主要集中在甘肃省黄土高原区南部。  相似文献   

16.
Genetic toxicity and carcinogenicity studies of glutaraldehyde--a review   总被引:2,自引:0,他引:2  
Glutaraldehyde is a high production volume chemical that is highly reactive and has many medical and industrial uses. The majority of human exposures are via inhalation, but the exposure is not widespread. It has been extensively tested for genetic activity in vitro and in vivo, and there is disagreement in the literature with regard to glutaraldehyde's genetic activity. Glutaraldehyde produced DNA damage in bacteria and some cultured mammalian cell systems. In vitro, it was mutagenic in Salmonella and E. coli, produced inconsistent positive responses in mammalian cells, weak and inconsistent responses in chromosome aberration and SCE studies, and did not induce transformation in cultured SHE cells. In vivo, inhalation of glutaraldehyde induced cell proliferation in nasal tissue in rats and mice, but DNA damage and UDS were not induced at these sites in rats. Chromosome aberrations in bone marrow cells were reported in only one of eight studies using rats and mice, micronuclei were not induced in bone marrow cells of mice, and dominant lethal mutations were not induced in mice. Glutaraldehyde did not induce cell transformation in SHE cells in vitro. Bone marrow hyperplasia and low, but statistically significant, levels of leukemia were seen in one chronic drinking water study in rats, but not in a chronic inhalation study in rats or two chronic inhalation studies in mice.  相似文献   

17.
P Ernfors  C Wetmore  L Olson  H Persson 《Neuron》1990,5(4):511-526
Cells expressing mRNA for hippocampus-derived neurotrophic factor (HDNF/NT-3) or brain-derived neurotrophic factor (BDNF) were identified by in situ hybridization. In the rat brain, HDNF mRNA was predominantly found in pyramidal neurons in CA1 and CA2 of the hippocampus. Lower levels of HDNF mRNA were found in granular neurons of the dentate gyrus and in neurons of the taenia tecta and induseum griseum. BDNF mRNA-expressing cells were more widely distributed in the rat brain, with high levels in neurons of CA2, CA3, and the hilar region of the dentate gyrus, in the external and internal pyramidal layers of the cerebral cortex, in the claustrum, and in one brainstem structure. Lower levels were seen in CA1 and in the granular layer of the hippocampus, in the taenia tecta, and in the mammillary complex. In peripheral tissues, HDNF mRNA was found in glomerular cells in the kidney, secretory cells in the male rat submandibular gland, and epithelial cells in secondary and tertiary follicles in the ovary. Cells expressing BDNF mRNA were found in the dorsal root ganglia, where neurons of various sizes were labeled.  相似文献   

18.
Observations on granulocyte peroxidase of 123 teleosts are reported and correlated with previous studies to put occurrence of fish granulocyte peroxidase in a phylogenetic perspective. Eosinophil peroxidase occurs in archaic groups such as lungfish and sturgeons, but is usually weak and infrequently observed in chondrichthyans, and in teleosts occurs in some elopomorphs, is consistently observed in stomiiforms, is rarely observed and usually weak in acanthopterygians and absent from salmoniforms, scopelomorphs and paracanthopterygians. Peroxidase is absent from lungfish and sturgeon neutrophils, is present in neutrophils of some elopomorphs and clupeimorphs. both of which are basal teleost groups, but in salmoniforms and higher teleosts is consistently observed in neutrophils. although often weak in pleuronectiforms.
Loss of eosinophil peroxidase and development of neutrophil peroxidase in teleosts may be due to inefficient phagocytosis and loss of peroxidase with degranulation in eosinophils, being superseded by concentration of peroxidase in phagosomes in neutrophils.  相似文献   

19.
The laminar distribution of binding to a number of postsynaptic neurotransmitter receptors was assessed autoradiographically in postmortem samples of area 23a in posterior cingulate cortex from 13 Alzheimer and nine age-matched control cases. Specific binding in all Alzheimer cases was compared to that in control cases, and the following alterations were observed: reduced muscimol binding in most layers; no changes in pirenzepine binding; and elevated cyanopindolol binding in layers Ic, IIIc, and IV. The Alzheimer cases were classified further on the basis of neuronal degeneration: class 1, no neuron loss; class 2, greatest losses in layer II or III; class 3, greatest losses in layer IV; and class 4, greatest losses in layer V or VI. This classification uncovered further alterations in ligand binding patterns. First, muscimol binding was reduced in layers II and III only in class 2 cases and in layers V and VI only in class 4 cases. Second, pirenzepine binding was reduced in layers Ic, IIIa-b, and VI of class 1 cases and layers Va and VI of class 4 cases. In spite of neuron degeneration in classes 2 and 3, there was no change in pirenzepine binding in these classes. Third, elevated cyanopindolol binding occurred in classes 3 and 4, whereas classes 1 and 2 had normal levels of binding. These results suggest that cases of Alzheimer's disease express heterogeneities in neocortical pathology which are reflected in the laminar patterns of binding to postsynaptic receptors. Reductions in muscimol binding to the gamma-aminobutyric acidA receptor had the closest relationship with neuron degeneration, whereas pirenzepine binding appeared to reflect a compensation in muscarinic receptors for changes in neuron densities.  相似文献   

20.
The neuropeptide oxytocin has been implicated in the regulation of affiliative behavior and maternal responsiveness in several mammalian species. Rodent species vary considerably in the expression of juvenile alloparental behavior. For example, alloparental behavior is spontaneous in juvenile female prairie voles (approximately 20 days of age), takes 1-3 days of pup exposure to develop in juvenile rats, and is nearly absent in juvenile mice and meadow voles. Here, we tested the hypothesis that species differences in pup responsiveness in juvenile rodents are associated with oxytocin receptor (OTR) density in specific brain regions. We found that OTR density in the nucleus accumbens (NA) is highest in juvenile prairie voles, intermediate in juvenile rats, and lowest in juvenile mice and meadow voles. In the caudate putamen (CP), OTR binding was highest in prairie voles, intermediate in rats and meadow voles, and lowest in mice. In contrast, the lateral septum (LS) shows an opposite pattern, with OTR binding being high in mice and meadow voles and low in prairie voles and rats. Thus, alloparental responsiveness in juvenile rodents is positively correlated with OTR density in the NA and CP and negatively correlated with OTR density in the LS. We then investigated whether a similar receptor-behavior relationship exists among juvenile female prairie voles by correlating individual variation in alloparental behavior with variation in OTR density. The time spent adopting crouching postures, the most distinctive component of alloparental behavior in juveniles, was positively correlated with OTR density in the NA (r = 0.47) and CP (r = 0.45) and negatively correlated with OTR density in the lateral septum (r = -0.53). Thus, variation in OTR density in the NA, CP, and LS may underlie both species and individual differences in alloparental care in rodents.  相似文献   

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